Rooney Mara and Joaquin Phoenix have welcomed their first child into the world. The couple has named their boy after Phoenix’s late brother, River.

Joaquin Phoenix, Rooney Mara, RiverKevork Djansezian / Getty Images

Russian filmmaker Victor Kossakovsky broke the news during a recent Q&A at the 2020 Zurich Film Festival. He said Phoenix could not be in attendance to promote the documentary Gunda, which Phoenix executive produced, because of the birth of his son, River.

“He just got a baby, by the way, his name was...a beautiful son named River, so he cannot promote it now,” Kossakovsky said on stage.

The director also explained that Phoenix’s Oscar acceptance speech from earlier this year is what inspired him to reach out for help on the film.

In his acceptance speech, Phoenix discussed animal rights. He also mentioned his late brother: “When he was 17, my brother wrote this lyric, he said, ‘Run to the rescue with love, and peace will follow.’”

Phoenix also spoke about River in an interview with 60 Minutes in January: "I feel like in virtually every movie that I made, there was a connection to River in some way. And I think that we've all felt his presence and guidance in our lives in numerous ways."